1. Field of the Invention
The present relates to the art of concrete construction and provides a formwork component for use in concrete construction of walls or the like. The formwork component is adapted to be connected to a plurality of corresponding formwork components for the formation of a shuttering. Such components comprise two parallel panel members interconnected by transverse cross members, the space between the panels being to be filled with concrete for the erection of a wall, e.g. of a building. Finally, the formwork components remain at their places and the panel members act as an insulating layer on the wall surface.
2. Prior Art
Formwork components of the kind described above are known e.g. from the Austrian Pat. No. 326'879 and from the Swiss Pat. No. 519'066. However, the voluminous cross members interconnecting the two panel members are embedded in relatively large projections provided on the inner surface of the two panel members. Thereby, these panel members, made of foamed, hardened plastic material, do not have an even, flat inner surface at all. The projections cause weakened portions in the wall to be erected, which are to be avoided in the interest of good fire protection and sufficient acoustic insulation, but also in view of the fixing of any elements on the finished wall. Furthermore, the static strength of such walls is much less than would be theoretically possible and the freedom in designing the wall dimensions is severely limited due to the coarse screening of the framework components, rendering it difficult to cut individual components to a desired size.
The aforementioned disadvantages are even more pronounced at a formwork component according to Swiss Pat. No. 616'981, which comprises integral cross members made of foamed plastic, because there will result continuous "holes" in the wall once the concrete is filled in and hardened.
A formwork component according to the Austrian Pat. No. 322'804 avoid these "holes", but has the disadvantage of providing cross members made of asbestos which have to be cemented to the panel members in the tension zone. The reliability and durability of such construction is doubtful and there remains the problem to cut the component at the desired position. Evidently, the formwork component according to the last mentioned Austrian Patent is very similar to shuttering elements to be assembled on the construction site, which is not desirable due to economic reasons.